Cheap headphones quickly break down, but a branded headset is expensive. If you have several broken sets lying around in your closet, your find can be considered a success. From individual parts you can assemble a good headset. First, the spare parts are checked for functionality, then they begin to assemble them. Now we will look in detail at how to make headphones and what is needed for this.

Main stages of headset assembly

The headphone assembly process consists of four stages:

• checking the integrity of the cable and the functionality of the speakers with a multimeter;
• soldering the wire to the plug;
• soldering bifurcated wires to the speakers;
• installation of parts inside the housing.

If you decide to assemble a headset for a mobile phone, one more item is added to the assembly process - soldering the microphone. All parts are taken from old broken headphones or bought in a store. The second option is not profitable, since the costs will exceed the cost of a new headset, and there is no point in assembling it yourself.

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Parts required for assembly

You can see what parts you need from your old headphones. Let's look at each node separately.

Plug for connecting to the connector of an electronic device

Headphones are connected to a mobile phone, player or computer using a plug. Its diameter corresponds to the size of a 3.5 mm jack. Another name for the plug is often used – mini-jack. The part is made in the form of a rod from composite elements. These are contacts that separate dielectric washers from each other. The number of contacts depends on the type of headset:

• 2 contacts have a monophonic headset plug;
• 3 pins on the stereo headphone plug;
• 4 pins on a stereo headset with microphone.

It is important to choose the correct plug according to the number of contacts, otherwise one of the elements of the headset may remain unconnected.

Cable

Headphones require a multi-core cable. The length is determined at your discretion. Any wire shape is suitable - round or flat. It is important that the cores match the number of parts of the headset. For simple headphones, a cable with 3–4 cores is suitable. To assemble a headset with a microphone, you will need a wire with 4–5 cores. It's not difficult to figure out how to connect them. Each core is covered with multi-colored insulation. Typically, the yellow wire is used for grounding, and wires with a different coating color are considered signal wires.

Speakers

The sound quality depends on the quality of the speakers. Depending on the type of radiation, a part can be low-frequency or high-frequency. Speakers are also divided into dome and simple. The last option is most often used in inexpensive headphones. Simple speakers do not have much power and sensitivity, but they are reliable.

It is difficult to buy the part separately. It's easier to take speakers from a broken headset. It is important to consider their size. The speakers must fit inside the body of the future headphones.

How to distinguish original Beats headphones from fakes

Microphone

When making a headset for a mobile phone, you will need a microphone. It is better to bite it off with wire cutters along with a piece of wire from old headphones. The microphone is housed in a sealed plastic box. Additionally, there may be a call button or volume control. To avoid cutting the boxes, leave a piece of wire 3–5 cm long on the input and output sides. The main cable of the headset is soldered to these pieces. The color of the veins must match.

Disassembling an old headset

To get all the necessary parts, they disassemble old headphones. You must act carefully, otherwise you may damage the parts. Large headphones have many hidden fastenings in the form of screws and latches. Most of them are hidden under a soft lining. The ear pads also come with snaps, they are simply put on the rim of the cup or glued. The body of the vacuum plugs will only have to be cut.

The old wire from the speakers is soldered off with a soldering iron. At the entrance to the housing, the integrity of the cores is compromised due to frequent kinks. If the cable is to be used for a new headset, then the ends, 5 cm long, are cut off and then the wires are soldered back to the speaker contacts.

A similar action is performed with the plug. If the mini-jack is non-separable, the casing is cut with a knife, and a new one is made from the cap of a ballpoint pen.

Diagnostics of parts for performance

When assembling headphones from old parts, they are checked for functionality. It is better not to ignore the procedure, because with the assembled headset it will be more difficult to identify a non-functioning element. Diagnostics is performed with a multimeter. First, check the passage of current through all cable cores. It wouldn’t hurt to check the contacts on the plug for closedness. If the dielectric ring is damaged, the headphones will not work.

The speakers are checked in the same way as the wire. The multimeter probes are placed against the contacts. If the speaker of the working device gives a signal.

Assembling new headphones

When all the parts have been selected and checked for functionality with a multimeter, begin assembling the headset:

• Soldering starts with the plug. On the back of the mini-jack, the longest pin is reserved for the ground wire. The signal wires of the right and left channels are connected to the side contacts. If the headset has a microphone, then the plug is used with four contacts to connect another signal core.
• After soldering the plug, the wire with the contacts is tested with a tester. If there is a signal, you can put on the cover. In a homemade design, the cap of a ballpoint pen is coated with epoxy resin and the back of the mini-jack is inserted.
• The branching conductors at the second end of the cable are pulled through the input holes of the headphone housing. The insulation is stripped from the ends of the wire, the copper wires are tinned with tin, and then soldered to the speaker contacts.
• At this stage, the functionality of the headset is checked. The plug is connected to a mobile phone on which a music file is played. If both channels are working, the speakers are immersed inside the headphone housing.
• The headset is almost ready, but there is still a microphone left. Just below the beginning of the bifurcation the cable is cut. The wire braid is stripped to free the cores. A similar stripping action is performed on the ends of the cable protruding from the microphone box. A heat-shrinkable tube is put on all the cores and soldered, matching the color of the insulation. The tubes are pushed onto the soldering site, after which they are heated with a lighter.
• Extended wire looks ugly. If you try, the microphone box will be cut with a knife along the solder line. The pieces of cable are unsoldered from the board with contacts, and the wire strands of the new headphones are soldered in their place. After checking the functionality, the halves of the microphone box are glued together.

The headset assembly is complete, you can enjoy music.

Headphones are a device that tends to break completely unexpectedly and out of place. Usually new headphones are bought immediately, because today it is quite difficult to imagine life without headphones. New headphones don't last any longer than old ones; Thus, in a few years you can collect a whole bag of headphones of varying degrees of damage. You shouldn’t throw them away - as a rule, from a bag of non-working headphones you can easily collect half a bag of fully functional devices.

Making headphones from scratch with your own hands is a difficult and very pointless task. One way or another, you will end up with a headphone assembly consisting of four components - a plug, a cable, speakers and a housing. Everything except the housing will probably have to be bought at a radio store or cut off from old headphones - and the housing, probably, too, unless, of course, you have some kind of original idea and especially straight hands. Nobody forbids casting a new case from plastic - but is the game worth the candle?

Assembling new headphones from a pair of old ones is a task without any special tricks. To do this, you only need a sharp utility knife, a soldering iron and a roll of electrical tape.

Studying the device of headphones

Before you start assembling the headphones yourself, it’s worth understanding what this device consists of and how it works.

Standard headphones, whether in-ear or on-ear, consist of three main elements:

So, the design of the headphones is very simple, so disassembling the old ones and assembling new headphones will not be an impossible task. But before you cut your old non-working headphones into pieces, you need to find out why they don’t work, what can be used from them and what cannot.

Spare parts diagnostics

Broken headphones may not work for many reasons. First, before you dissect the device, make sure that they are not actually working - perhaps the problem is not with them at all, but with the sound source you are using.

If the headphones themselves definitely don’t work, find out which part is inoperative and which parts can be used. The main causes of breakdowns are wires coming loose from the plug contacts, cable rupture and speaker failure. Thus, you may need three pairs of broken headphones to assemble new working ones - from one you will take a plug, from another - a cable, from the third - a housing with speakers.

We disassemble old headphones

Prepare broken headphones for work and find a suitable tool:

• sharp knife for stripping and cutting wires;
• soldering iron for connecting wires to contacts and fixing twists;
• insulating tape or heat shrink pad for connecting cable sections.

In the last step, you found out which parts are suitable for further use - feel free to chop up the headphones and separate these working parts. The plug must be cut so that at least 3 cm of the old cable extends from it. Speakers are cut off in the same way.

If you can’t find a working plug, cut it completely: remove the plastic case and tear off the remaining wires from the contacts; they will no longer be useful.

The old cable does not have to be intact. Let's say it was too short, and in new headphones you want to extend it, or in all old headphones it is torn. It doesn’t matter - take as many pieces as you find - connecting them is not difficult at all.

How long should the cable be?

The standard length of the headphone cable is 80–120 cm. In this case, a good range is also ensured - the sound source is rarely located far from the headphone body, and the influence of the cable on the sound quality is vanishingly small. If you make the cable longer, signal loss is quite possible, leading to distortion, interference and squeaking in the headphones. A shorter cable will simply be inconvenient.

Is a cable needed at all? Is it possible to do it yourself? wireless headphones? Well, this is, of course, possible, but it is better to do this if the old headphones were wireless - in this case, you can use a working transmitter by inserting it into the case with working speakers. Adding a wireless interface to previously wired headphones is difficult for an inexperienced user - you will need to create a control chip and program it.

Assembling new headphones with your own hands

So, you have received a complete set of working spare parts - it doesn’t matter whether they were obtained from old headphones or bought in a store. All that remains is to assemble them correctly, and you can start listening to music.

Plug

First of all, let's deal with the plug. Its attachment can occur in two ways:

• if it worked, then the piece of wire coming from it is simply connected to the rest of the cable;
• If a non-working plug is taken, it will have to be disassembled and thoroughly connected to a new cable.

Let's look at the second situation in more detail. The design of the plug is simple and not particularly deep - in principle, there is nothing to break there, so even if it no longer works as part of the headphones, it itself is quite functional and can be used again.

Beneath the plastic casing you will find a metal base of the plug from which two or more metal plates of varying lengths extend. In the case of conventional stereo headphones, there will be three plates - two contacts for transmitting the left and right channels and a contact for grounding. The third contact is the easiest to identify - it is the longest and is usually attached to the sleeve - the long part of the plug extending from the base.

We take a cable or one of the parts of the future cable and strip one of its ends. Under the braid you can find 3 or more often 4 wires, which are again stripped of insulation. After this, using a soldering iron, you should melt the transparent protective layer so that the current passes as freely as possible. After this, the wires are connected to their contacts - the channels can be safely swapped, this will not affect anything. The copper wires are twisted, wound to the contacts and secured with a blowtorch. Remember that the wires must be insulated from each other.

The plug body cannot be restored, but you can use anything instead - just wrap the twist with electrical tape or thread the plug into the tip of a syringe or a pen cap.

Cable

If the cable is assembled from several sections, its parts will have to be securely twisted together. To do this, the parts to be connected are freed from the braiding, and the wires are stripped of insulation. After this, the wires are twisted in a linear or spiral manner - detailed instructions there is no need here, this operation is easily performed on a whim. Then the twist is fastened with a soldering iron, the channels are isolated from each other and from the ground. The top of the twist is wrapped with electrical tape or tightened with heat shrink tape. The main thing is to match the color to the braid so that the cable does not look too handmade. As a last resort, you can make a homemade winding of thread or lacing over the plastic braid.

Speaker

All that remains is to connect the speaker. Disassemble the case using any in a convenient way– it is best if such a possibility is provided and the body parts are fastened with screws that can be unscrewed.

On the body of the emitter itself you will find the same contacts as on the plug. The corresponding channel is connected to one of them, and the ground is connected to the second. We solder, insulate, and put the case back together.

Thus, from several non-working pairs of headphones, it is easy to assemble new headphones with your own hands using a simple set of tools. There is no point in assembling headphones from scratch - it will be easier (and, as a rule, cheaper) to simply buy them at the nearest store.

Hello dear friends. Today the subject of my review will be these inexpensive and high-quality headphones.
Let's start with the fact that I needed high-quality headphones for my computer. By the quality of headphones, I mean, first of all, high-quality sound and secondly, reliability and durability of the design. Naturally with a minimal budget.

After a long and painstaking task, such as looking through dozens of other models, reading hundreds of reviews, and choosing a price, I settled on this model. And as it turned out, I was right. Everything I needed was here. The sound is very high quality, the reliability of the design is simply amazing.
Unfortunately, I cannot convey the sound quality and listening experience to you through video. But you can trust my extensive experience that the sound is just super! And if you trust me and acquire this model, then I give you my word - you will definitely not be disappointed. The bass is smooth and soft. The sound is spacious and warm. The noise isolation of the headphones from external sounds is very good - little of the external noise can be heard through the headphones.
Well, I described the sound as best I could, now about the design. The headphones themselves are full size... Not small, not big - just what you need. After reading hundreds of reviews, I realized that most Chinese headphones have a flimsy and unreliable design. This is expressed in tearing off and bending the headphones themselves in the middle (on the jumper) or tearing off one of their “ears” or even the wire.

This model is protected from these factors and features due to its design. They can easily be bent in the middle and there will be nothing wrong with them, as you can see. The headphones are trimmed with artificial leather, very pleasant to the touch. The headphones have a universal size and adapt to the size of any head.

Another defect with most headphones is the wire coming off or even being pulled out. This especially often happens when a person is sitting with headphones on at the computer and suddenly gets up and forgets to take off the headphones. I think this is familiar to many. Look at this high-quality wire with protection against fractures - to tear it off you need to apply more than tens of kilograms. You definitely won’t be able to do this accidentally (tear off the wire).
You probably have a question - why are there 2 plugs and also USB? – I’ll answer: 1 plug is the headphones themselves, the second is the microphone. These are computer, gaming headphones with a microphone - here is a microphone. USB is a stylish backlight.

The headphones come in two colors: light and dark, I took the dark model. Headphone diameter 50 mm, resistance 32 Ohm, reproduced frequency range - 20-20000 Hz, sensitivity - 107 dB. The cost of headphones is around a thousand - for high-quality headphones, I think this is very cheap.

In general, you shouldn’t save on this and look for even cheaper ones. As you know: disappointment from Low quality lasts longer than the joy of a low price. So take it – you won’t regret it. If in doubt, add to cart. Thanks for watching this video. Like, subscribe to the channel - see you again.

Headphones -

Hundreds of millions of people have long been unable to imagine their lives without music. Every day you can see men and women in public transport using headphones to listen to their favorite songs. All this, of course, is great, but, unfortunately, the headset breaks down very, very often. It is for this reason that many users ask one question: how to make headphones with your own hands at home? The question is quite relevant, since in all the variety of available models you can only rely on yourself.

We make a headset for listening

Where should I start? In order to understand how to make headphones with your own hands, we recommend that you refer to the following instructions:

• Purchase an output type that will fully meet the requirements of the audio source jack ( mobile device or computer). Today we can distinguish one most common type - miniJack. The diameter of such a pin is either 6.3 mm or 3.5 mm. The first is used mainly in stationary home appliances, and the second in mobile portable equipment. But let's not forget that every rule has its exception.
• Now remove the housing cover on the purchased plug. Next, pass through the hole in this cover a very durable and high-quality cable, which should have four cores.
• Then locate the post on the surface of the plug that is used to secure the wire. This stand is equipped with a special hole. Solder half of the conductors in the cable to this hole. There will be two conductors left. Solder them to two small pins. Also, put special small tubes on them in advance for insulation.
• Next, wrap the wire with electrical tape and secure the wrapped section in the rack.
• Close the plug and use the most common ohmmeter to check the device for short circuits (short circuits).
• Get two small speakers with the same diameter. The resistance of each of them should be eight ohms. Install these speakers in special round resonator housings. To carry out this operation, you can use small plastic jars. Next, connect one 30 ohm resistor in series.
• Now take care of the headband. Make it from some metal ruler. Place and fix the emitters on this structure. There are several ways to do this step. different ways, for example, you can use a nut and screws.

Important! Please note that sharp protruding parts may harm your health in the future, so such elements should be avoided.

• Now connect two wires to each emitter. Connect the first of these wires to the post of your plug, and the second to one of its small contacts.

Now you know how to assemble headphones with your own hands, but is it possible to achieve the same result in another way?

Making a new headset from a broken old one

Nobody forbids you to use another method to create a new device. To carry out the work you will need the following tools:

• Sharp scissors.
• Broken headphones.
• Soldering Station.
• Insulating tape.

Important! The result is guaranteed only if at least one of the headphone speakers is in working condition.

To carry out the work, you must follow the following instructions:

• Use a sharp blade or sharp scissors to remove the plastic part from your plug.
• Using the same sharp object, strip the insulation from the wires and use a soldering iron to connect the wires to the corresponding connectors on the plug.

Important! Please note that optimal signal transmission will occur only through soldered wires, since “twisting” will cause you to lose the useful part of the signal. It should also be taken into account that during the union the pairs have the same color.

• If the defect that caused the headset to malfunction occurred within the design of the device, it should be replaced with another one. Use another broken pair for this. If for any reason the wires become unsoldered from the membrane, use the soldering iron again.

Important! Try not to mix up the left and right speakers while working.

If all actions have been completed according to the instructions, then all that remains is to check the functionality of the new device on some sound source (laptop, PC, mobile phone or tablet).

Video material

Now you know how to make two headphones for your phone different ways. Take on work only if you are confident in your abilities. Read the instructions carefully and do not neglect safety measures.

Manufacturing of structural parts and assembly of emitters. Membrane. Mylar film from K73-16 capacitors is well suited as a membrane material. This is a wonderful base in many ways, with the exception of one drawback - its width is only 35 mm, which imposes certain restrictions on the area and shape of the membrane. In capacitors for an operating voltage of 100 V, the film thickness is 4...5 microns.

How to make your own headphones

This is quite enough for an amateur design. After all, even with such a film thickness, its mass, as follows from, is comparable to the mass of oscillating air. The capacitance value of the capacitor does not matter; it is important that the length of the capacitor body is 48 mm. This is the maximum possible size, and the width of the film removed from such a capacitor is exactly 35 mm.

Of course, if it is possible to use a film of similar properties of suitable sizes, then the task of manufacturing a larger-sized membrane is significantly simplified. However, the option with a capacitor film, although problematic from a technological point of view, is quite accessible and requires separate consideration. To do this, you can refer to, where the manufacture of a membrane for TDS-7 phones is described in detail. In relation to this case, the revised part of the description looks like this: Carefully saw along the capacitor body and take out its “filling”.

We unwind and remove the initial part of the roll 20...30 cm long, where a thick film is used as a dielectric. Next, the working part of the capacitor actually begins, which consists of two films folded together (capacitor plates). We cut a strip 15 cm long from the roll. Using a sharp scalpel, we separate the films from each other. The main difficulty is to “catch” to the beginning of the section of films fused together.

Next, to facilitate the process, you can drop a few drops of acetone into the gap formed between the films. After the films are separated, the metallization should be removed from them. In this case, you can use ordinary bleach, the process time is 20 minutes.

After which the films should be thoroughly washed, dried and ironed with a hot iron (temperature for wool) through a sheet of paper, preferably just between the sheets in a book. The output of the process is transparent, even, smooth films suitable for use. To obtain the desired width of the membrane, the resulting two films must be glued together. Unlike the method described in this case, gluing must be done overlapping.

Let's do it like this.

We place the previously prepared films, as described above, on a flat, smooth surface and connect them together with their long sides with an overlap of 1.5...2 mm. Holding them in this position and bending one of the sides, we apply BF-6 glue a little at a time (literally in micro portions) along the line of film overlap. You can press immediately. In this case, it is better to start gluing from the middle. This method is more labor-intensive than others, but in terms of seam strength the result is much better.

In addition, the adhesive layer is protected on both sides from the active influence of the working coating (spraying) of the membrane. To eliminate irregularities, the film thus obtained must also be ironed again. In this case, the adhesive seam should be isolated from the paper with Mylar film (from a roll), otherwise the heated glue, if it ends up outside the seam, will stick to the paper sheet. After heat treatment, microfolds may appear on the film as a result of eliminating irregularities. The main thing is that the resulting film should be completely flat without bulges or warping. One should not hope that in the future, when stretching it on an insulator, such defects will be corrected.

The thickness of the adhesive seam after smoothing with a heated iron is approximately 20 microns, and its influence on the total mass of the film is minimal, and the strength of such gluing is quite sufficient.

After trimming, a workpiece with dimensions of 70x120 mm is obtained with an adhesive seam running along the axis of symmetry (Fig. 2). It should be added that it is better to stock up on such semi-finished products for future use so that in case of failure you do not have to repeat the whole process again.

Despite the fact that the film removed from the capacitor is initially metallized, the issue of coating the membrane is not decided in favor of its native conductive coating. And there are two reasons for this. Firstly, one-sided metallization, as in this case, leads to curling of the film, which is practically impossible to eliminate, which is very inconvenient to work with and ultimately leads to warping of the membrane.

Secondly, an extremely thin layer of metallization is prone to complete loss of conductivity at fractures, in particular at the output lobe, which, in turn, leads to loss of performance of the entire emitter as a whole. Therefore, removing metallization, as described in, does not contradict the general idea in this case.

So, the semi-finished product in the form of a smooth, without signs of warping, transparent film with the indicated dimensions is ready, and now you can proceed to the next stage - the stage of membrane spraying. Judging by the debates on thematic forums, the technology for manufacturing proprietary membranes remains a secret, and, perhaps, they are not feasible at the amateur radio level, nevertheless, there are a lot of ideas. One of the most accessible methods of coating a substrate is spraying antistatic agent “Lana” or other aerosols with similar physical properties.

This coating is classified as high-resistivity, and its resistivity is 2...5 GOhm/cm². And despite the fact that such a coating is presented as a trial, temporary one, in fact the end result in relation to GT can be quite acceptable. Thus, almost all prototypes, subject to the manufacturing technology, worked without serious complaints about such deposition. However, it was not possible to estimate the lifetime of such sputtering.

Some samples worked successfully for more than a year without reducing sensitivity, after which, one way or another, they underwent modernization. It should also be noted that such membranes are unpretentious to storage in the cold (-30 °C) or at elevated temperatures (+50 °C). 100% humidity (followed by drying) is also satisfactory. Over time, the resistivity of such a coating tends to increase, which can lead to a noticeable increase in the time of charge accumulation on the membrane from the moment the polarizer is turned on.

The spraying process is quite simple. First you need to make a protective frame from thin, even cardboard. The frame is needed so that the jet from the sprayer hits only the working area of ​​the film. In Fig. 2 this area is highlighted gray. It is better to reduce the internal dimensions of the frame by 0.5... 1 mm to limit the transition area of ​​deposition. The indicated cuts on the membrane petal are made immediately before stretching it on the insulator or during the stretching process, in place. We apply the frame to the film and spray it from a distance of 20...25 cm.

This should be done moderately, so that there are no sagging on the film. The antistatic agent is active against BF-6 glue, but the latter is already protected by layers of films. The operation must be repeated twice with an interval of 2 hours. The opposite side of the membrane should be sprayed in the same way. It is recommended to cover the petal with an additional layer or even two, since problems associated with decreased sensitivity due to

Convenient to use are self-tapping screws with flat heads of the specified diameter, clamped along the thread with “crocodiles” of a voltmeter. Of course, these voltage values ​​are indicative and depend on the properties of the antistatic agent, which may differ from one manufacturer to another. In this case we are talking about the products of the Novomoskovsk plant. If necessary, the number of spray layers can be increased. The principle is simple - the thinner the layers, the more there are.

But an antistatic agent such as Lyra is less preferable. A coating based on it has a noticeably higher resistivity and may ultimately be comparable to the leakage resistance of the entire structure, which will complicate the task. For example, in the previous measurement scheme, the voltmeter readings may be in the range of millivolts. In addition, “Lyra” is more sticky, which creates certain problems.

Fixed electrodes

From one-sided foil-coated fiberglass laminate with a thickness of 1.5 mm, we cut out two identical blanks according to the dimensions of the finished electrode, as in Fig. 4. Both NEs - internal and external - are the same, except that on the external (farthest from the ear) electrode, instead of mounting holes with a diameter of 2 mm, as shown in Fig. 4, make M2 threaded holes.

There is no need to drill the mounting holes yet. But you can drill holes for perforation using a stationary drilling machine at the same time. To do this, both parts must be pressed against each other with their foil sides and a stencil must be applied to them. The package thus obtained is secured with miniature clamps. Holes should be drilled within the boundaries of the foil area, with the exception of the outlet petal.
At the end of drilling, the package is separated, burrs on the drilled electrodes are removed with a fine file and sandpaper. After this, you may have to go through all the holes again with a drill to clean out the holes. Ultimately, the working surfaces of the NE must be, as they say, in perfect condition. If you plan to use a hand-held electric drill, then in order to avoid possible distortions of the NE holes, it is better to drill separately, one at a time.

The next stage is the production of insulators. To do this, you will need one-sided foil fiberglass (the use of getinax is allowed) with a thickness along the width of the selected gap. Let this be a compromise option from the previously indicated values, for example 0.8 mm, from the standard range of fiberglass laminate grade SF-1. Of course, the gap and thickness of the NE can be chosen differently based on available materials or for other reasons.

This will basically only lead to a change in the thickness of the emitter, which is easy to take into account in the future. The sensitivity is adjusted by selecting the polarization voltage. For one emitter you will need two parts - A and B, as in Fig. 5. Insulator B is shown only in fragments (lower part), and non-foil fiberglass laminate can be used for its manufacture, otherwise the parts are identical.

You can cut the insulators with a regular cutter, having previously drilled holes in the corners with a thin drill. Afterwards, the foil should be removed, with the exception of the area highlighted in color (Fig. 5), this is the contact pad for gluing the membrane petal and soldering the cable conductor.
The cutout in the lower part of insulator B is designed to prevent the adhesive contact between the membrane petal and the contact pad from being deformed when assembling the package. If foil fiberglass laminate of the specified thickness is not available, the contact tab can be cut out of copper foil and glued in place with “Moment” universal glue.

Then, with epoxy glue (a plasticizer is required), the insulators are glued to the inner (foil) sides of the stators, and the petal of insulator A should be directed in the same direction as the foil side of its stator. In order to save material, insulators can be made from individual strips 5 mm wide. In this case, it is better to use a mandrel in the form of a thin rectangular plastic plate with dimensions of 50x85 mm, which guarantees good repeatability of the internal dimensions of the insulator frames. After drying, possible sagging of epoxy glue on the working surfaces of the stators must be removed.

Now you can drill the mounting holes and it is better to do this simultaneously on both NEs, precisely aligning them with insulators to each other and securing them with clamps. First, you should drill through holes with a diameter of 1.5 mm. Then disconnect the NE and drill holes up to 2 mm on the inner (closest to the ear) electrode, and cut an M2 thread on the outer one using the first tap number. Ultimately, the package will be held together with M2 screws 5 mm long with a countersunk head. Therefore, on the outside of the internal electrode it is necessary to make countersinking holes for the screw heads. Threads in fiberglass laminate have reliability limitations, and this must be kept in mind when assembling the package.

Upon completion of all work related to mechanical processing, the parts should be thoroughly cleaned of dust and degreased. Before painting conductive surfaces, NE insulators must be protected with adhesive tape from paint getting on them. After painting, you should pay attention to the quality of the coating. Hard inclusions protruding above the surface, which sometimes still occur, must be cleaned off.

Emitter assembly

At this stage, first of all, you should correctly stretch the membrane, which is attached to the NE with insulator A. This is an important point on which the success of the work as a whole depends. Stretching the membrane itself is not so complicated or time-consuming. Much more difficult work to adjust its tension when you have to partially peel off the membrane. In this case, film tears are possible. Therefore, it is desirable that the required result is obtained the first time. You can first practice on a dummy - uncoated film, which you don’t mind. Acquiring a certain skill plays a decisive role. In extreme cases, you can use a film with a thickness of 10 microns. This film is used in K73-16 capacitors for a rated voltage of 400 V.

The prepared membrane is carefully placed on the stator so that its sprayed part is exactly above the perforation of the electrode, and its petal coincides with the foil section of the insulator. In Fig. 6 numbers indicate the sequence of actions.

First, at point 1 on the end side of the stator, apply a smear of “Moment” universal glue and after 10...20 s, bend and fix the upper edge of the membrane on it. Next, at points 5 and 8, you also need to apply light dotted strokes of glue on the end. After exposure, fix the lower part of the membrane with moderate tension in the direction of the arrows. There is no need to be particularly zealous with glue.

The film is lightweight and holds well even with minimal use. After waiting for about 10 minutes, lightly coat the end sections 1-2 and 1-11 with a thin layer of glue (hereinafter indicated by thick lines). Again, hold for 10...20 s - and the upper edge of the membrane is folded onto the end of the NE with simultaneous tension in the direction of the arrows. The same operation is performed with bottom membranes (areas 5-6 and 7-8).

Thus, the vertical stretch is completed. In this case, the middle part of the membrane should be flat, longitudinal (vertical) waves can only be at its edges. After a longer exposure of up to 30 minutes, you can do a wide stretch. To do this, apply a thin layer of glue to section 3-4 of the stator end along its entire length. Hold for 10...20 s - and also bend the side edge of the membrane to the end along the entire length with a tension slightly greater than necessary to eliminate waves.

Again, hold for 10 minutes, after which the opposite edge of the membrane is glued to the other end of the electrode in the same way (section 9-10). The result of the work performed should be a completely flat membrane without waves or folds. You can blow lightly on the membrane, making sure that there are no vibrations in its individual sections. The better the quality of the membrane, the fewer problems there are when stretching it.

“Moment” glue holds the tension of the membrane well, while allowing you to correct a possible defect. To do this, you will need acetone, but it should be used in minimal portions so that it does not flow onto the sprayed part of the membrane, otherwise leaks may occur, which can often be eliminated only by replacing the membrane itself. But if the defect is noticed even at the moment of gluing, when the glue has not yet completely adhered, then you can quickly separate a section of the film from the insulator without resorting to acetone. A NE with a membrane stretched on it is shown in Fig. 7.

Now you can roughly evaluate the quality of the membrane tension by listening to its resonant response when you tap the electrode with your finger. A “flabby” sound indicates that the tension is too weak, while a ringing sound, on the contrary, indicates that the tension is too high. The sound should be low in tone and elastic. Generally speaking, it is better to over-tighten the membrane slightly than under-tighten.

Ultimately, the somewhat larger losses at frequencies below 40...50 Hz are not as important as the consequences of a membrane that is too loosely tensioned. These include a rather unpleasant phenomenon that occurs when the gap is small or due to excessively weak tension of the membrane - its relaxation vibrations, and sometimes sticking to one of the NEs. The reason for this phenomenon is that in the event of an asymmetry in the position of the membrane in the gap, a difference force acts on it, tending to attract the membrane to the NE that is closest to it at the moment.

But as follows from communications on Internet forums, even branded products are not immune from this. Then, at the point of contact of the membrane petal with the foil section of the insulator, a little conductive glue should be applied so as to ensure contact with the foil of both sides of the membrane petal, cutting off its excess, as shown in Fig. 8 (fragment of NE).

Such contact, despite its apparent dubiousness given the oily properties of “Lana,” is in fact quite reliable. The remaining free corner of the insulator lead is intended for soldering a conductor with a polarizing voltage of +Uо. You can also prepare a conductive adhesive paste yourself by thickly mixing fine copper filings filed with a file into a drop of PF-283 varnish. This paste hardens quickly and should be prepared immediately before use.